The present invention relates to fuel admitting and conditioning means on combustion chambers for gas turbine engines, where the respective flame tube of a combustion chamber is provided in the upstream area with circumferentially equally spaced primary air supply ports.
With known embodiments of combustion chambers for gas turbine engines, the fuel is finely atomized under great pressure by means of known simplex or duplex nozzles and is injected into the primary zone where it is conditioned, i.e., transformed to a vapor state for subsequent combustion, or it is admitted into the primary zone by means of air-operated atomizer nozzles, where air is admixed to the fuel often while still in the nozzle so as to expedite the conditioning process.
For admitting and conditioning fuel it is also known practice to employ various types of vaporizing burners, in which the fuel is transformed into a gaseous state, as a result of the elevated wall temperature caused by the combustion process and of the flow conditions, and is premixed with air.
These known fuel injecting and conditioning devices, however, are all characterized in that combustion generaly proceeds from one point and that, therefore, forcible mixing processes and related devices are needed to achieve a uniform combustion chamber outlet temperature profile.
This type of spot injection further requires relatively long combustion chambers to achieve spatially uniform fuel conditioning for uniform combustion, or it requires intensive swirling in the primary zone of the fuel and air contents to force relatively uniform combustion while still in the primary zone, although this boosts the pressure losses and, thus, impairs the engine performance.
In a broad aspect the present invention provides a fuel admitting and conditioning means which eliminates the disadvantages in the previously cited means, reduces the installed length of the combustion chamber for less installed volume and, thus, less weight of a gas turbine engine, and achieves a more uniform temperature profile at the turbine exit by optimally conditioning the fuel/air mixture.
The means provided by this invention further enables a greater load to be imposed on the combustion chamber than could be imposed heretobefore.
The present invention contemplates providing fuel admitting and conditioning means where the fuel is admitted through fuel tubes projecting from above or laterally into primary air supply ports. In this manner, the fuel is entrained by the primary air as it passes through the primary air supply ports.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken on connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.